The present invention relates to a vehicle body.
In particular, the present invention relates to an aluminum vehicle body, to which the following description refers purely by way of example.
As is known, in recent years, there has been a marked increase in the number of vehicle models featuring aluminum bodies this tendency is due to the fact that, for a given structural strength, aluminum bodies are much lighter than conventional steel bodies and so provide for a drastic reduction in the overall weight of the vehicle and, hence, in fuel consumption and, more importantly, in polluting emissions by the vehicle.
The downside of all these advantages, however, is the extremely high production cost involved, which is why aluminum bodies are limited solely to higher-range vehicles.
As is known, all vehicle bodies, regardless of the material used, comprise a floor panel and a number of posts, to some of which the vehicle doors are hinged. In the case of aluminum bodies, the process employed to assemble the posts, particularly those to which the doors are hinged, is highly complex and expensive and accounts for a large part of the overall production cost of the body.
The post manufacturing process currently adopted by all car manufacturers, by reputedly being the best, is to produce the post in a number of parts, which are welded together prior to final assembly to the body. If the post is to support a door, the body of the post is bolted or welded with hinges to which the door is then fixed.
More specifically, in a first tested solution, each post comprises an extruded, constant-section, central tubular member; two butts welded to the two ends of the tubular member to connect the tubular member to the other body members; and a number of reinforcing members welded to the more severely mechanically stressed portions of the post.
For cost reasons, the above solution has been replaced over the past few years with one in which, as shown in FIG. 1, each post I is divided into two a complementary half-shells Ia and Ib, one cast and the other pressed, which are welded and/or riveted together, with the resulting whole welded or riveted, if necessary, with the door hinges.
Both the first and second solution have the major drawback of involving a good deal of welding, which, in the case of aluminum, must be performed in an inert atmosphere at considerable cost. Moreover, the presence of a large number of welds on a part increases the likelihood of fatigue failure, so that manufacturers are forced to use materials of a thickness well in excess of the minimum thickness theoretically required.
It is an object of the present invention to provide an aluminium vehicle body which, as compared with known types, is cheaper to produce and provides for greater structural strength.
According to the present invention, there is provided a vehicle body comprising a floor panel and at least one post projecting from said floor panel; the body being characterized in that said post is defined by a box member having an inner cavity and formed in one piece using a casting process.